Paris: A huge, potentially life-giving sea
likely covered more than a third of Mars some 3.5 billion
years ago, according to a study released today.
Spread over an area the size of the Atlantic Ocean, it
would have straddled the North Pole and contained the
equivalent of a tenth of the water on Earth.
For decades scientists have argued as to whether the Red
Planet once harboured bodies of water big enough to help
nourish a true hydrological cycle marked by evaporation and
Recent evidence suggests as much, but doubts remained.
To dig deeper, Gaetano Di Achille and Brian Hynek of the
University of Colorodo in Boulder sifted through huge stores
of images collected by NASA`s Mars Orbiter Laser Altimeter
(MOLA) in the late 1990s and other more recent European and US
satellite-based monitoring systems.
The data was not new, but the researchers were the first
to link up all available information on Mars` terrain into a
single computer-driven model.
The study, published in Nature Geoscience, found 52
river-delta deposits scattered across the planet.
More than half occurred at about the same elevation, and
thus probably marked the boundary of the once-massive sea.
All of these would have been connected either directly to
the ocean, or to its groundwater table along with several
large, adjacent lakes.